Concave suspension control system and method for a threshing section in a harvesting machine

ABSTRACT

A method of positioning a concave in a threshing section of an agricultural machine including the steps of selecting and maintaining. The selecting step includes the selecting of a set pressure, a minimum separation distance of the concave from a rotating member and a maximum separation distance of the concave from the rotating member. The maintaining step includes the maintaining of a hydraulic fluid pressure in a hydraulic concave support system that supports the concave at substantially the set pressure while the concave is positioned between the minimum separation distance and the maximum separation distance when crop material is being transported between the concave and the rotating member.

FIELD OF THE INVENTION

The present invention relates to a harvesting machine, and, moreparticularly, to a harvesting machine with a concave suspension controlsystem for the threshing section.

BACKGROUND OF THE INVENTION

Harvesting systems, also known as combines include a crop gatheringportion that gathers the crop material and separates it from the ground.In the threshing section the desired grain is threshed from the materialgathered. The threshing system includes what are known as concaves thatare positioned proximate to a moving usually somewhat cylindrical rotor.The concaves include holes through which the grain passes during thethreshing session. The grain is then conveyed for further processing andtemporary storage within the harvesting system.

During the harvesting operation the feed rate of crop material into thethreshing section of the harvester is highly variable. This is causedboth by operator selections of such things as the ground speed but alsothe feed variability due to variation in the crop density and presenceof weeds. This variable feed rate presents a problem for the harvestingmachine settings as well as the component life of the concaves and otherthreshing devices.

When a harvester is set up for a specific crop, that setting is finetuned for a particular throughput of the machine. This particularthroughput is selected to work best for a specific throughput of themachine. However, the actual throughputs of the machine will varysignificantly from the ideal throughput. When the harvester is operatingwith the selected setting it is not optimized when not operating at thatspecific throughput for which the setting was designed. This results inless than optimum performance which is expressed in increased losses,grain damage, excess strain on the components and wear on the threshingconcaves and other components therein. Further if the feed ratevariation occurs at a rate faster than which the operator can react,such as slug feeding, the threshing section undergoes extreme stress.This stress leads to component failure of the mechanical systems. Themechanical components as a result are designed to take the highestpossible loads even though machines will typically not see these loadsunder normal operation and some machines will never see these loads.

What is needed in the art is an adaptive and effective threshing controlsystem for use in a harvester.

SUMMARY OF THE INVENTION

The present invention provides a hydraulic suspension control system forthe concaves associated with a rotor in a threshing section of aharvester.

The invention in one form is directed to a method of positioning aconcave in a threshing section of an agricultural machine includingsteps of selecting and maintaining. The selecting step includes theselecting of a set pressure, a minimum separation distance of theconcave from a rotating member and a maximum separation distance of theconcave from the rotating member. The maintaining step includes themaintaining of a hydraulic fluid pressure in a hydraulic concave supportsystem that supports the concave at substantially the set pressure whilethe concave is positioned between the minimum separation distance andthe maximum separation distance when crop material is being transportedbetween the concave and the rotating member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a harvesting machine utilizing an embodiment ofthe present invention;

FIG. 2 is a partially sectioned side view of threshing section utilizingan embodiment of the present invention;

FIG. 3 is a schematicized end view of the threshing section illustratingelements of an embodiment of the hydraulic concave support system of thepresent invention;

FIG. 4 is another end view of another embodiment of the hydraulicconcave support system of the present invention;

FIG. 5 is a side view of either FIG. 3 or FIG. 4; and

FIG. 6 is a schematical block diagram illustrating some of the controlelements of the hydraulic concave support system of FIGS. 1-5.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, and more particularly to FIG. 1, there isshown a harvesting system 10 having wheels 12, a frame 14, a cab 16, acontrol system 18 and a threshing system 20. Wheels 12 are connected toframe 14 providing for movement of system 10. Frame 14 supports cab 16and threshing system 20. Within cab 16 part of control system 18 islocated including an operator interface.

Now, additionally referring to FIGS. 2-6 there is shown elements ofthreshing system 20. Rotor 22 also known as a rotating member 22 rotatesabout an axis drawing crop material thereinto and threshing it betweenrotor 22 and concaves 26, which are supported by hydraulic concavesupport system 24. Hydraulic concave support system 24 includes hangerpipes 28 also known as support bars 28, guides 30, stop bolts 32,position sensors 34 and hydraulic cylinders 36. For ease of illustrationrotating member 22 has been drawn as a rotor 22, but rotating member 22may also be understood to include a cylinder in a cylinder threshingsystem. Concaves 26 move in a direction substantially toward or awayfrom rotor 22 as constrained by guides 30. At least one portion, eitherthe ram/piston or the body of hydraulic cylinders 36 travel in thedirection of travel of concave 26.

Referring now to FIGS. 3 and 5, there is shown one embodiment of thepresent invention where hydraulic cylinders 36 are connected to hangerpipes 28 with at least one concave 26 positioned on hanger pipes 28.Hydraulic cylinders 36 are operatively controlled to position concaves26 so that they are proximate to rotor 22 with the minimum of clearanceeven with a clearance of zero millimeters thereby coming very close torotor 22. Hydraulic cylinders 36 control the position of concave 26while the harvesting process is ongoing. Guides 30 are positioned sothat the hanger pipes 28 traveling along a desired path. Stop bolts 32contact hanger pipe 28 to physically stop the movement of concave 26 anyfurther in the vertical direction. In the illustrated embodiment,hydraulic cylinders 36 are directly connected to a respective hangerpipe 28 without any linkages to change the direction of movement of themovable hydraulic element of hydraulic cylinder 36, which moves insubstantially the same direction as concave 26. The functioning of thehydraulic system and how it controls the support of concave 26 will bediscussed later after next considering another embodiment of hydraulicconcave support system 24.

Now referring to FIGS. 4 and 5 there is shown another embodiment of thehydraulic concave support system 24 having a support 38 with a pivotpoint 40 and a hydraulic cylinder 36. In FIG. 4 one hydraulic cylindermay be utilized which may be centrally located along hanger pipe 28.However, it is also contemplated to use two hydraulic cylinders asillustrated in FIG. 5 along one side of rotor 22. Although hydraulicconcave support system 24 is illustrated and described as supportingconcave 26 from beneath concave 26, it is also contemplated that thepresent invention can be embodied as a suspension system with concave 26being suspended from hydraulic cylinders 36 that are suspended from asupport positioned above concave 26.

In FIG. 5 there are shown further details including locating features 44that extend from a part of hydraulic cylinders 36 and extend throughopenings 42 in hanger pipe 28. Cam lock pins 46 extend through concave26 in such a manner that when concave 26 is inserted, while hydrauliccylinders 36 are fully contracted, the cam lock pins 46 extend upwardand when the operator commands the extension of hydraulic cylinders 36the cam lock pins 46 contact lock protrusions 48 causing the cam lockpins 46 to rotate into the position shown in FIG. 5 where two portionsof cam lock pins 46 extend into and through openings in concave 26. Whenit is time to change concaves 26 the operator causes hydraulic cylinders36 to fully contract causing unlock protrusions 50 to extend throughholes in hanger pipe 28 thereby pushing cam lock pins 46 into anunlocked position for easy removal of concaves 26 from threshing system20.

Now, additionally referring to FIG. 6 there are shown schematically someof the elements of hydraulic concave support system 24 including acontroller 62, an operator interface 64, actuators 66, 68, 70 and 72,sensors 74, 76, 78 and 80, accumulators 82 and 84, and valves 86 and 88.Actuators 66, 68, 70 and 72 are individually identified hydrauliccylinders 36 that are identified as such for the ease of discussion.Operator interface 64 is located in cab 16 and allows the operator toprovide input into the positioning and setup of hydraulic concavesupport system 24. Controller 62 receives position and pressureinformation from sensors 74, 76, 78 and 80 to operatively controlhydraulic concave support system 24. Accumulators 82 and 84 arepositioned to absorb certain pressure and fluid imbalances in thesystem. Accumulators 82 and 84 are hydraulically connected on thenon-shaft side of hydraulic cylinders 36 as illustrated in FIG. 5.Valves 84 and 86 are positioned on the shaft side in order to controlthe rate at which concave 26 approaches rotor 22. Although accumulator82 and valve 86 are shown along a side of concave 26 in FIG. 5 it isalso contemplated to utilize this configuration with the hydrauliccylinders that are across from each other as shown in FIG. 3.

While sensor, 74, 76, 78 and 80 may include both pressure and positionaloutputs to controller 62 and may be integral with the respectiveactuator, it is also contemplated that the sensors may not be integralwith the actuators. For example, there may be one positional sensorassociated with a hanger pipe 28 or one actuator. Also, one pressuresensor per hydraulic circuit, apart from the actuators, is alsocontemplated.

As the crop material enters into threshing system 20 hydraulic concavesupport system 24 functions to keep a substantially constant pressure onconcaves 26 as concave 26 may vary in position from rotor 22 dependingupon the bulk of the material passing therethrough. If concave 26departs from rotor 22 more than a predetermined amount then hydraulicconcave support system 24 increases the pressure to maintain the spacingso that it does not exceed the predetermined departure from rotor 22.However, if the pressure measured by sensors 74, 76, 78 or 80 exceed apredetermined value then controller 62 allows hydraulic cylinders 36 tomove concave 26 away from rotor 22 until the material causing thesignificant pressure is moved through threshing system 20. Valves 86 and88 control the rate at which hydraulic cylinders 36 return to theirdesired position so that concave 26 does not come into too rapid contactwith crop material or rotor 22.

Concave 26 can be supported utilizing hydraulic concave support system24 on one side with the other side mounted to support 38 as shown inFIG. 4 or concave 26 may be hydraulically supported on both sides, asshown in FIG. 3. Hydraulic concave support system 24 utilizes multiplehydraulic cylinders 36 attached to a single hanger pipe 28 havingconcave 26 supported thereby. An accumulator is hydraulically connectedto hydraulic cylinders 36 to maintain a pressure on the crop mat as itflows through threshing section 20. This pressure on the crop matprovides for more variability in the feeding rates as the thin mat willhave substantially the same pressure as a thick mat as it flows throughthreshing system 20. The prior art method of adjusting the distancebetween the concaves and the threshing elements is not the criteriafollowed by hydraulic concave support system 24 which tries to maintainthe concave clearance at zero millimeters. As the crop passes throughthreshing system 20 the departure of concave 26 from rotor 22 isadjusted by hydraulic concave support system 24 to the desired croppressure. In the event of a concave overload hydraulic concave supportsystem 24 drops concave 26 to allow the obstruction/slug to passtherethrough. One way of detecting the presence of a slug may be therate of concave displacement, in which controller 62 detects the rate ofchange allowing for a rapid opening of concave 26 from rotor 22 to allowthe obstruction to pass without damage to threshing system 20.

In another embodiment of the present invention, the operator enters adesired pressure to be maintained on the crop mat, and a minimum andmaximum opening distance for the distance between concave 26 and rotor22. These settings are crop specific and operator interface 64 maydisplay suggested settings for a particular crop type/variety.Controller 62 positions concave 26 at the minimum opening distance, suchas 5 mm, when there is no crop mat between concave 26 and rotor 22.Controller 62 monitors the separation distance as the crop mat flowsbetween concave 26 and rotor 22 and maintains the desired pressure aslong as the separation distance remains between the minimum and maximumopening distance. If the maximum opening distance, such as 15 mm, isapproached or violated, then controller 62 increases the pressure tomaintain the separation distance so as to not exceed the maximum openingdistance, even if the pressure exceeds the selected pressure. However,if a blockage or slug enters between concave 26 and rotor 22, controller26 detects this and rapidly moves concave 26 away from rotor 22 to allowthe blockage/slug to pass. The detection of the blockage/slug isaccomplished by detecting a high rate of change in the separationdistance and/or by a rapid pressure increase and/or exceeding apredetermined pressure sensed by at least one of the sensors 74, 76, 78or 80. Once the blockage/slug has passed, controller 62 moves concave 26back to its normal operating position between the minimum and maximumopening distance. The passing of the blockage/slug is assumed after apredetermined amount of time. Alternatively, the passage of theblockage/slug is detected by moving concave 26 toward rotor 22 whilemonitoring the pressure being applied by actuators 66, 68, 70 and/or 72.

Applicants also contemplate the use of a predetermined pressure profileor use of an algorithm to modify the pressure applied to concave 26while it is between the minimum and maximum opening distance.

Operator interface 64 allows the operator to advantageously cam lock andunlock concave 26 when it is time to change out concave 26. Operatorinterface 64 additionally allows the desired pressure to be set by theoperator while hydraulic concave support system 24 does attempt tomaintain the concave clearance at zero rather than a preset separationas in the prior art.

The present invention advantageously reduces crop loads on the threshingsystem and the concave support structure as well as provides for betterserviceability and more crop throughput while keeping crop losses to aminimum. The reduced loading in the system is beneficial in that somestructural members can be reduced in size and weight to provide anoverall improvement in the efficiency of the system. The single pointrelease utilizing the cam lock system can be advantageously operatedfrom the cab and reduces the changeover time when concaves have to bereplaced or are changed to accommodate a different crop. Anotheradvantage of the present invention is that the harvester is able tomatch the changing conditions without operator input and is able toprovide a more uniform loss curve while varying the feed ratestherethrough. Yet a further advantage of the present invention is thatit reduces concave wear that can be brought on by incorrect operatorsettings of a concave clearance.

Having described the preferred embodiment, it will become apparent thatvarious modifications can be made without departing from the scope ofthe invention as defined in the accompanying claims.

1. An agricultural harvesting machine, comprising: a frame; and athreshing section supported by said frame, said threshing sectionincluding: a rotating member; a concave; and a hydraulic concave supportsystem positioning said at least one concave proximate to said rotatingmember, said hydraulic concave support system including a controllerconfigured to execute the steps of: selecting a set pressure, a minimumseparation distance of said concave from said rotating member and amaximum separation distance of said concave from said rotating member;and maintaining a hydraulic fluid pressure in said hydraulic concavesupport system at substantially said set pressure while said concave ispositioned between said minimum separation distance and said maximumseparation distance when crop material is being transported between saidconcave and said rotating member.
 2. The agricultural harvesting machineof claim 1, wherein said controller further executes the step ofpositioning said concave no closer to said rotating member than saidminimum separation distance.
 3. The agricultural harvesting machine ofclaim 2, wherein said controller further executes the step of increasingsaid hydraulic fluid pressure dependant on a proximity of said concaveto said maximum separation distance.
 4. The agricultural harvestingmachine of claim 2, wherein said controller further executes the step ofdetecting one of a blockage and a slug.
 5. The agricultural harvestingmachine of claim 4, wherein said controller further executes the step ofmoving said concave beyond said maximum separation distance if saiddetecting step does detect one of a blockage and a slug.
 6. Theagricultural harvesting machine of claim 5, wherein said controllerfurther executes the step of returning said concave to be between saidminimum separation distance and said maximum separation distance.
 7. Theagricultural harvesting machine of claim 6, wherein said returning stepis carried out after one of a predetermined time after said moving stepand a detection that one of said blockage and said slug has passedbeyond said concave.
 8. The agricultural harvesting machine of claim 4,wherein said detecting step includes measuring a rate of change ofposition of said concave.
 9. The agricultural harvesting machine ofclaim 4, wherein said detecting step includes measuring a rate of changeof pressure of said hydraulic pressure.
 10. The agricultural harvestingmachine of claim 1, wherein said controller further executes the stepsof: measuring a pressure of said hydraulic fluid; and moving saidconcave beyond said maximum separation distance if said pressure is morethan a predetermined value.
 11. A method of positioning a concave in athreshing section of an agricultural machine, comprising the steps of:selecting a set pressure, a minimum separation distance of the concavefrom a rotating member and a maximum separation distance of the concavefrom the rotating member; and maintaining a hydraulic fluid pressure ina hydraulic concave support system that supports the concave atsubstantially said set pressure while the concave is positioned betweensaid minimum separation distance and said maximum separation distancewhen crop material is being transported between the concave and therotating member.
 12. The method of claim 11, further comprising the stepof positioning the concave no closer to the rotating member than saidminimum separation distance.
 13. The method of claim 12, furthercomprising the step of increasing said hydraulic fluid pressuredependant on a proximity of the concave to said maximum separationdistance.
 14. The method of claim 12, further comprising the step ofdetecting one of a blockage and a slug.
 15. The method of claim 14,further comprising the step of moving the concave beyond said maximumseparation distance if said detecting step does detect one of a blockageand a slug.
 16. The method of claim 15, further comprising the step ofreturning the concave to be between said minimum separation distance andsaid maximum separation distance.
 17. The method of claim 16, whereinsaid returning step is carried out after one of a predetermined timeafter said moving step and a detection that one of said blockage andsaid slug has passed beyond the concave.
 18. The method of claim 14,wherein said detecting step includes measuring a rate of change ofposition of the concave.
 19. The method of claim 14, wherein saiddetecting step includes measuring a rate of change of pressure of saidhydraulic pressure.
 20. The method of claim 11, further comprising thesteps of: measuring a pressure of said hydraulic fluid; and moving theconcave beyond said maximum separation distance if said pressure is morethan a predetermined value.